This protocol was designed to test whether IL-2 can act as an immunologic adjuvant in the active specific immunization of patients with metastatic renal cell cancer. Stage IV patients whose primary renal tumors have not been removed or who have otherwise easily accessible tumor are taken to the operating room, where tumor is obtained and processed into a single cell vaccine. After recovering from surgery, patients are given 3 autologous tumor vaccines at weekly intervals. The first two vaccines consist of BCG and autologous tumor cells and the final vaccine is composed of tumor cells alone. Patients are randomized to receive no IL-2, low-dose IL-2 or high-dose IL-2 administered subcutaneously during the vaccination period. Seventeen patients have been treated on this protocol, of whom fourteen are evaluable for delayed type hypersensitivity (DTH) testing. Four of fourteen developed positive DTH responses. Two patients experienced partial remissions; both received high dose IL-2 during vaccination and had regression of parenchymal lung or pleural lesions. In addition, one patient who was treated with subcutaneous IL-2 after vaccination had a dramatic response, perhaps reflecting potentiation of a subclinical vaccine effect.